Characteristics of gas exchange and chlorophyll fluorescence in red and green leaves of Begonia semperflorens

Abstract

To determine the effects of leaf colour on gas exchange and chlorophyll fluorescence, two genotypes of Begonia semperflorens with green leaves or red leaves were compared. The red leaves showed a high accumulation of anthocyanins and high absorbance at 282 and 537 nm while the green leaves exhibited a higher net photosynthetic rate and lower thermal dissipation of light energy. It seems likely that anthocyanins in the vacuoles restricted the absorption of green light to the chloroplasts, leading to a decrease in the efficiency of excitation capture by open PS 2 centres, photochemical quenching and CO2 assimilation.

Keywords

• anthocyanins
• net photosynthetic rate
• non-photochemical quenching
• photochemical quenching
• rubisco